摘要
基于WBM模型,耦合热力学数据库,建立了相场模型,模拟了Ti-43Al合金L→β定向凝固过程中微观组织的演化。讨论了相场参数以及凝固参数对界面形态的影响。结果表明,各向异性系数越小,尖端生长越慢,侧枝生长相对容易,易于形成胞状晶;减小界面厚度,溶质易于在胞晶间凹槽处富集,导致浅胞状枝晶向深胞状转变;随温度梯度增大,界面形态的演化模式为:深胞-浅胞-平界面。
The phase field modeling of L →βdirectional solidification in Ti-43A1 binary alloy was estab- lished by coupling the thermodynamic databases to WBM model. Based on the model, the microstructure evolution in solidification process was successfully simulated. The influences of phase field parameters and solidification parameters on the interracial morphology were analyzed. The simulated results show that, with the decrease of the anisotropy coefficient, the tip growth rate is decreased and branch growth is easier, which is in favor of formation of cellular structures. The grain growth is transformed from shallow cell to deep cell as a result of easy enrichment of solute at groove of cell grain with the interface thickness decrease. In addition, with the increase of the temperature gradient, the interracial micro- structure evolution is transformed from deep cell to shallow cell, then to planar interface.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2013年第2期119-123,共5页
Special Casting & Nonferrous Alloys
基金
国家重点基础研究发展计划(973计划)资助项目(2011CB610404)
关键词
钛铝合金
定向凝固
相场
界面形态
Ti-Al Alloy, Directional Solidification, Phase-Field, Interfacial Morphology
作者简介
黄春丽，女，1987年出生，硕士研究生，西北工业大学凝固技术国家重点实验室，西安（710072），电话：029-88490294，E-mail：huangchunli--2006@163．com
通信作者：常辉，男，1969年出生，副教授，西北工业大学凝固技术国家重点实验室，西安（710072），电话：029-88491764，E-mail：ch2006@nwpu．edu．cn
